The Sword Art Online anime is an anime adaptation of the original Sword Art Online light novel series, written by Kawahara Reki. The anime is produced by A-1 Pictures, with the direction of Tomohiko Ito. It began airing on July 7, 2012 in Japan, while an English dub version began airing on July 27, 2013. A second season, titled Sword Art Online II, started airing on July 5, 2014.[1] An original Sword Art Online movie, titled Sword Art Online The Movie -Ordinal Scale-, was released on February 18, 2017 in Japan, as well as various other countries. A third season, adapting the Alicization Arc, was announced Dengeki Bunko Autumn Festival, along with an anime for the Sword Art Online Alternative: Gun Gale Online spin-off, which will begin airing in April 2018.

Sword Art Online has been officially released as the first VRMMORPG. Kirito, a beta-tester of the game, returns to the world of Aincrad to meet a beginner named Klein to whom he teaches the basics. Later, as they try to log out, they find that they are trapped within the game. After being teleported back to the starting town, Kayaba Akihiko appears as the game master and tells them that he has purposely removed the log-out button with the intention of having them clear all 100 floors. As Akihiko leaves, he reveals the player's true identities through a mirror that he placed in their inventory. Kirito leaves the starting town with only the thought of survival in mind because he knows that the rest of the beta testers will dry out the good hunting grounds. Before leaving, Kirito asks Klein to follow him to which Klein declines, saying that he was going to wait for his friends in the starting city. By the end of the first month, 2,000 out of the initial 10,000 are dead with the first floor yet to be cleared.

A month has passed since the game started, 2,000 people are already dead, but they haven't cleared the first floor yet. To deal with this situation the first floor boss strategy meeting commences. The meeting is directed by a player named Diavel, after a brief talk everyone was told to make parties, since he didn't knew anyone Kirito allied with a girl named Asuna. A guy called Kibaou interrupts the meeting, but after a man named Agil interferes the meeting is resumed. That night Kirito talks to Asuna and the next they head to the boss room. During the fight Diavel commands everyone and the battle flows as planned, but at the last moment Diavel attacks the boss alone but it made an unexpected move, and takes him down with a single blow. Kirito then attacks the boss, and with Asuna and Agil's help he defeats it. Kibaou then confronts him for being a beta tester, creating discomfort between the other players, so Kirito takes all the blame to himself, takes the title of Beater and leaves to the second floor.

After four months inside the game, Kirito has reached well above level 40. After assisting a small group of players on a lower floor, Kirito is asked to join their guild, the Moonlit Black Cats. When asked about his level, Kirito lied and told them that he was around level 20. Kirito was told to train Sachi to use a one-handed sword. Eventually, Sachi confesses to Kirito that she is afraid of dying. Kirito promises her that he would never let her die. Sachi begins to sleep in Kirito's room because she felt safe. After days of leveling, the group had almost reached a level capable of fighting on the frontlines. On June 12, 2023 Keita, the guild leader, decides that it was time to buy a small house to act as the guild's headquarters. While he was gone, the remaining party members decided to go into a higher level dungeon to surprise Keita with new items when he comes back. While in the dungeons, the group stumbles upon a hidden room that contained a treasure chest. Not heeding Kirito's warnings, the group opens the chest and triggers a trap. Kirito watches as all of the members die and especially feels guilty for Sachi's death. After learning of the news, Keita commits suicide by jumping off the side of the town.

During Christmas, Argo the Rat reveals to Kirito a special quest that yielded an item that could revive the dead. Kirito heads off to face Nicholas The Renegade. He bumps into Klein and his guild and later the Holy Dragon Alliance. Klein tells Kirito to go face the boss while he held off the Holy Dragon Alliance. After defeating the boss, Kirito learns that the revival item only worked on a person within 10 seconds of their death. He gives the revival item to Klein and leaves to go sulk in his room. Suddenly, a recorder crystal shows up in his inventory. Upon activation, Sachi's voice tells Kirito to not blame himself for her death. She was glad that she had met him and that he had wanted to protect her. She then sings him "Rudolph the Red Nosed Reindeer" before telling him to live on.

Kirito finds a beast tamer named Silica, who just lost her familiar, Pina, and decides to help her recover it. On the way to the Inn, he finds out that she's very famous, loved by some and hated by others. While explaining the procedure to recover Pina, he discovers someone eavesdropping on them. The next day he helped Silica gain some levels on their way to the Pneuma Flower needed to revive Pina. After they find the flower, they're ambushed by the Titan's Hand guild, who want the flower. After Kirito explains his motives, he is attacked by the members of the guild, but he overwhelms them with his high level and finally sends them to Prison. At the Inn, he talks with Silica and they agree to meet in the real world and Silica finally reincarnates Pina.

Kirito is sleeping in the outskirts of a Town and Asuna arrives to wake him up, but Asuna falls asleep and Kirito watches for her. To thank him, she invites him to dinner, but they hear a scream, just to discover someone was killed inside the Safe Area. They start investigating and find various clues, but nothing seems to explain how that man was killed, so they talk to Agil. After Agil tells them that the sword was made by a player called Grimlock they talk to Yolko at a cafe, who tells them about her former guild the Golden Apple. They decide that they must also talk to another member of the guild, Schmitt, and they invite him to Yolko's room in an Inn. After a brief talk, Yolko loses her composure and near a window, she suddenly turns and falls with a dagger stabbed on her back. Kirito rushes to safe her, but he only manages to see her disappear in polygons on the floor.

After Yolko falls from the window Kirito looks in the roof nearby and starts chasing a hooded player and tries to capture him, but the player teleports away. After dispatching Schmitt they have dinner, Asuna made Kirito drop his sandwich and when he sees it disappear figures out everything. He realized that Yolko and Cainz were alive and they were trying to trick Schimitt to make him confess what he did. They were ambushed by the Laughing Coffin top three but Kirito arrived just in time and save them. Later Asuna finds Grimlock and brings him to them to confess that he planned Griselda's murder. Schmitt and the others take Grimlock, leaving Kirito and Asuna alone, before leaving they see Griselda's ghost giving thanks to them.

Looking for a sword that can rival his Elucidator, Kirito visits a shop run by Asuna's friend Lisbeth. During his visit he proves that Lisbeth's strongest sword is not strong enough by accidentally breaking it. After a little chat he and Lisbeth decide to look for a mysterious material that is said to be obtainable in a quest on floor 55. When they arrive Kirito confronts a White Dragon. However, Lisbeth is blown away so Kirito jumps to save her, with both of them falling into a pit. Unable to get out, where they spend the night there. The next morning Kirito finds the ingot they were looking for. When the dragon returns, Kirito takes Lisbeth and rides the Dragon to outside the pit. On Lisbeth's shop he gives the ingot to her and she makes a new sword called Dark Repulser. Before Lisbeth can express her feelings to Kirito, Asuna arrives and Lisbeth realizes that she is also in love with him. Lisbeth runs away to hide her feelings but Kirito finds her and comforts her promising that she'll be his exclusive blacksmith.

Kirito gets a rare and very valuable ingredient, since he can't cook it he visits Agil and tries to sell it, during their conversation Asuna arrives, and tells them that she mastered the cooking skill. After Kirito shows her the rare ingredient they depart to Asuna's home, after eating and chatting Kirito leaves. The next day Kirito is waiting, and suddenly Asuna appears, followed by her bodyguard, Kuradeel who was watching outside her house. The bodyguard tries to take Asuna back, but when he's stopped by Kirito, decides to challenge him to a duel, however Kirito breaks his sword easily and wins the duel. A few hours later, Kirito and Asuna are fighting in the dungeon in floor 74, they arrive at the boss room and open the door.

Kirito and Asuna enter the boss room to gather information, but after the starting sequence finishes they run all the way back to the Safe Area, where they talk while having lunch. Klein enters the area with his guild, and after a brief talk a squadron from The Army too, they request the map info from Kirito and he agrees. The Army's squadron departs toward the boss room, Kirito and company follow them, but when they finally reach the boss room the leader of the squadron is killed, and Asuna jumps in to safe the others, so Kirito follows, giving time to Fuurinkazan to save the others. After some hesitation, Kirito decides to reveal his secret, and after 10 seconds of changing his equipment, he enters back to the fight with his Dual Blades equipped. Kirito defeats The Gleam Eyes by himself, but only at the edge of death, he faints for a few seconds, when he recovers consciousness everybody is around him, and Asuna hugs him, Kirito explains about the Dual Blades to Klein and lets him activate the gate to the next floor. Asuna tells him that she'll take a break from her guild to be with Kirito; the next day Kirito is hiding in Agil's shop, when Asuna suddenly enters. In the Knights of Blood HQ, Kirito is challenged by their leader, Heathcliff, to decide Asuna's future.

Kirito accepted the duel against Heathcliff, and they finally meet in a stadium on the 75th Floor. It was an intense battle, but Kirito managed to find an opening in Heathcliff moves. However, just as he was about to deal the finishing blow, Heathcliff moved at an impossible speed, blocking his attack and striking him instead. Having lost the duel, Kirito joined the guild and told Asuna about his time with the Moonlit Black Cats. She promises to protect him, and they head to the KoB HQ where they learnt that Godfree was planning to take Kirito to a training in a dungeon on the 75th Floor by Heathcliff order. To his surprise, Kirito found out that Kuradeel would accompany them. Along the way, the group stopped to rest and eat, but Kirito and Godfree end up being paralyzed by a poison Kuradeel put in the water. Kuradeel then killed Godfree and revealed that he was part of Laughing Coffin. Just as he was about to kill Kirito, Asuna appeared and easily reduced Kuradeel's HP to the red zone. Kureadeel then seemingly surrendered and begged for mercy and, when Asuna lowered her guard, Kuradeel tried to attack her. But then Kirito jumped in time and killed Kuradeel with Embracer. Kirito then asked Asuna to spend the night together, to which she agreed. At Asuna's house, Kirito proposed to Asuna and she agreed.

Kirito and Asuna talked to Heathcliff and he let them leave the guild for a while, but ordered them that they should return to the frontlines soon. In their house in 22nd floor, Kirito asked Asuna if their love will only last as long as they're on the game, but she argued and told him that she'll look for him in the real world and will still love him. They spent time together in a forest until they found a girl who suddenly fell unconscious, which was the rumored 'ghost' in the 22nd floor. She's no ghost, nor a player, nor even an NPC. They took her to their house and took care of her until she woke up. She claimed that she doesn't remember anything, aside from her name "Yui". She can't say Asuna and Kirito's name, and she called them "Mama" and "Papa" instead. They believed that she got separated from her family, they went to the Town of Beginnings to look for her parents and for her to recover her memories. Instead, they find a young woman named Sasha and the children she's taking care of being harassed by the Army for not paying the taxes. Asuna attacked their leader and the soldiers ran away in fear. As Sasha and the children thanked her, Yui reached for the sky and kept saying "Everyone's heart...". Asuna rushed to Yui and asked if she remembered anything. Yui then tells Kirito and Asuna that she realizes she has never been to the Town of Beginnings before. Suddenly her eyes widened and mysterious static sound spread out and affected everyone before Yui faints.

Kirito, Yui and Asuna are in the first floor talking with Sasha about her duty taking care of the children and the recent events involving The Army, when a member of such guild arrives. She presents herself as Yulier and explains everything that has happened as she asks for help to rescue Thinker, the real leader of the Army, who was trapped in a high leveled dungeon hidden in the first floor. They enter the dungeon and Kirito enjoys himself killing everything along his way until they are able to see the safe zone where Thinker was, but when Yulier was running towards it, she was attacked by The Fatal Scythe. Kirito and Asuna save her, but they nearly die, when Yui saves them, destroying the monster. It is revealed that she is the mental health AI, and was driven insane by watching all the player's pain and doing nothing. She is about to be deleted by Aincrad's AI controller, Cardinal, when Kirito saves her into a small blue crystal.

While fishing near a lake, Kirito encounters Nishida, an old man and a network security manager who oversaw the game's development, who claimed that despite honing his fisherman skill, he is unable to create delicious dishes with them. Kirito then invites him to his home for Asuna to cook the fish he just caught for them. During their meal, Nishida mentions a huge fish he tried to catch many times but failed, thus he asks Kirito to help him. Nishida manages to hook the fish and gives the rod to Kirito to pull it away. The fish is revealed to be a huge monster whom Asuna slays. Soon after, Kirito receives a message from Heathcliff, and upon meeting him, they learn that a scouting party was trapped and killed in the 75th level's boss room, thus a team of players from several guilds is being assembled to confront it. As the time for the battle approaches, Kirito asks Asuna to stay behind fearing for her safety, but Asuna refuses, claiming that she would rather die than live without him. She also mentions that all players' real bodies must be currently treated in hospitals and their condition can not be kept indefinitely, thus fleeing to live by themselves trapped in the game forever is also out of question. As the players enter the boss room, they are confronted with "The Skull Reaper", a powerful monster capable of killing players with one blow. Kirito, Asuna and Heathcliff confront the creature head on while the other players attack it from the sides.

After the group defeats the Skull Reaper, losing 14 men in the process, Kirito deduces that Heathcliff is, in fact, Akihiko Kayaba himself. Paralysing everyone but Kirito, Akihiko offers Kirito the chance to face him in a one-on-one duel where, should Kirito win, Akihiko would log out all the remaining players. After giving his best wishes to the others, Kirito accepts the challenge but is unable to overcome Akihiko's advantage over him. As Akihiko prepares to make the final blow, Asuna overcomes her paralysis and takes the hit instead, losing all of her HP and disappearing as a result. Distraught by Asuna's death, Kirito loses the will to fight and receives a fatal stab from Akihiko. However, at the point of death, Kirito remembers Asuna's belief in him and manages to regain enough substance to defeat Akihiko using Asuna's sword. They are both killed simultaneously and the game is declared cleared. Kirito then awakens high above the game world where he finds both Asuna and Akihiko, who reveals he has logged out all the other players as promised and explains his motives for making Sword Art Online. As the world falls apart, Kirito and Asuna reveal their true names, Kirigaya Kazuto and Yuuki Asuna, and embrace each other as the world disappears. To his surprise, Kazuto awakens in a hospital in the real world and despite being physically weak, sets off to search for the real Asuna.

Two months after being freed from SAO, Kazuto continues to be plagued with nightmares about Asuna. Since his two-year coma in the game, his sister, Kirigaya Suguha, has been constantly worrying about him. The pair have a kendo spar, and though Kazuto loses, Suguha is both shocked and curious about his unusual yet proficient sword fighting skills as a result of his time in SAO. Later, Kazuto goes to the hospital to visit Asuna who, along with 300 other players, has yet to wake up even after the SAO incident. It is there that he meets an associate of Asuna's father, Sugou Nobuyuki, who tells Kazuto that he intends to be adopted into Asuna's family while she is still comatose as a precursor to marriage, much to Kazuto's fury. Claiming that this is his right since it was his company that had been keeping SAO's server online after it's developer went bankrupt, he's keeping Asuna alive, he informs Kazuto that the ceremony will occur in a week and tells him not to see her again. Later at home, Kazuto breaks down before Suguha, who tells him not to give up, despite knowing Kirito is actually her cousin and harboring her own feelings for him. The next morning, Kazuto receives an e-mail from Agil with a screenshot of an avatar resembling Asuna from another game.

Kazuto visits Agil to know more about the photo, and learns about a new game, SAO's successor, ALfheim Online and that Asuna might be in the game at a place called the World Tree. Kazuto goes home and starts to play the game. Due to malfunction of the game, Kirito is transported to a forest, and find that all of his SAO data was transferred into Alfheim along with Yui. Kirito learns the basic of flying from Yui. While two players called Leafa and Recon are attacked by a group of players causing Recon to die but when Leafa was surrounded, Kirito appears to rescue her.

Kirito killed two of the players and asked the last one if he wanted to fight, but he made an excuse before flying away. Kirito asked Leafa if she also wanted to fight, to which she declined. Leafa offered to buy Kirito a drink as a thank-you for saving her, so she took him to Swilvane, an Sylph town. There they met Recon, who had respawned there. He told her that Sigurd and the others had saved her a seat at their usual meeting place, but Leafa declined, explaining that she had promised Kirito a drink. At a tavern they go to, Kirito asked about the World Tree, and was told that there was a Grand Quest to clear it, and to receive unlimited flight, but Leafa thought that it was impossible. Kirito got angry, but calmed down and thanked Leafa, telling her he would go alone. When Kirito was about to leave, Leafa offered to take him. He thanked her, and she logged out. At this point, it was revealed that Leafa was Suguha. Kirito lay in bed with Yui at the tavern, and promises her that he would rescue Asuna and reunite them all. He then logs off by falling asleep.

Meanwhile, Asuna sat in a golden cage, and looked wistfully at the birds outside. Oberon (Sugou Nobuyuki) then approached her, and taunted her about the fact he was experimenting on the brains of the SAO players who had yet to wake. She told him that she would tell the police, but he told her that he would alter her memory as well. Asuna tried to read the door code as Oberon left, but was unable to due to the distance effect. Once he was gone, she cried out for Kirito to save her.

Suguha reminisces about how she started VR gaming, and then meets up with Recon's real life persona, Shinichi Nagata. She informs him that she will be leaving their party to join Kirito. Later, she logs in as Leafa and accompanies Kirito to shop for new equipment, but runs into her party. The group is led by Sigurd who does not take kindly to Leafa's departure and warns them they will be considered renegades for not sticking their allegiance to their race's territories. Before Kirito and Leafa set off, Recon approaches them, saying that though he wants to join them, he will remain in the party to keep an eye on Sigurd due to some suspicions he has on him. Later during their travels, Kirito and Leafa arrive at a landing point where they take turns logging out to refresh themselves. After Kirito returns, they both set off again, unaware that they are being followed by a mysterious group. Meanwhile, Asuna learns from Sugou that Kirito is still alive and secretly obtains the keycode for her cage's lock.

While passing though a cave, Leafa gets a message from Recon warning her to take care when she and Kirito realize that they are being followed and try to escape, only to cornered by a large group pertaining to the Salamander faction. Kirito asks Leafa to support him with her magic while he fights the group by himself, but he is unable to break their formation until Yui comes up with a plan to have Leafa cast some protective magic on Kirito while he conjures a spell that transforms him into a giant monster that obliterates the enemies, save for one whom Kirito bribes in exchange for information. He reveals that his party were sent to attack them by orders of the same group which attacked them when they first met. After arriving at the next town, Suguha logs out for a while and is called by Shinichi who reveals to her that Sigurd is in cahoots with the Salamanders, who threaten to attack the Sylphs and Cait Siths during a meeting to establish an alliance. Upon logging in again, Leafa explains the situation to Kirito and states that for his own sake, he should proceed without her, as allying with the Salamanders may be the best option for him in order to reach the top of the World Tree. Kirito instead claims he will not abandon her and makes use of his speed to break out of the cave with her.

Kirito and Leafa reach the meeting place just as the Salamanders prepare to attack the Sylphs and Cait Siths. Seeing that they have no chance against them, Leafa thanks Kirito for all he has done for her and asks him to continue to the World Tree by himself, but he rushes forward and stands before the Salamander General Eugene instead, bluffing that he is an ambassador for the Spriggans/Undines alliance and to attack them would lead to the four factions waging war against the Salamanders. Eugene does not believe him and challenges him to a duel. Kirito is severely punished by Eugene's sword which can bypass his defenses, until he conjures a huge smokescreen, making use of it to steal Leafa's sword and turn the tides of the battle fighting Eugene with two swords. After Eugene is defeated, he is revived by Sakuya, the leader of the Sylphs and leaves in peace with his army. Having his treason exposed, Sigurd is contacted by Sakuya who strips him of his title and has him banished from the Sylph territory. After learning that the now allied Sylphs and Cait Siths plan an incursion to the World Tree in a couple of days, Kirito donates a large sum of money to Alicia, leader of the Cait Siths, to aid them in their war effort and departs ahead with Leafa. Meanwhile, Asuna makes use of the code she had previously learned to open the cage and escape.

Kirito and Leafa finally arrive at Alne and a voice announces that there will be server maintenance soon. Kirito asks if there's a cheap inn because he gave away most of his cash to log out at and Yui points them to it. In the real world Kazuto greets Suguha and notices that she is sleepy. Suguha tells Kazuto she was up late on the internet and Kazuto pours cold water down her back. Meanwhile Asuna uses the code she learned to get out of her cage and tries to escape. While looking for a system console so she can log out she notices a map with a room marked experiment. Curious she heads there where she sees holograms of brains who seem like they are in pain. She vows to help them but notices a couple of scientists who logged in in the form of slimes. She heads towards the console but gets caught and thrown back in the cage but not before snagging a GM card.

Kirito rushes up the World Tree as high as he can but is blocked by the barrier set up by the moderators. As Yui calls out to Asuna, she hears her and throws down the key card to Kirito. Resolving to get to where Asuna is, Kirito decides to part from Leafa in order to take on the Grand Quest to reach the top of the tree himself. Upon entering the dome at the base of the tree, Kirito is faced with hundreds of valiant guardians, which he angrily battles against. Despite his best efforts, Kirito is overwhelmed and runs out of HP. Just then, Leafa manages to gather Kirito's flame, containing his soul, and get him out of the dome in order to revive him. As Leafa tries to talk Kirito out of going back in there alone, she hears him speak Asuna's name, leading Suguha to realise that Kirito is actually Kazuto. As they both realise each other's identities and log out, Suguha reveals to Kazuto both the fact that she fell in love with both of his identities and how she knew they weren't really siblings before shutting herself in her room.

In sorrow, Kirito remembers how he discovered the truth about his parents, and the reason he started playing video games. After a moment of solitude, he tells Suguha to meet him at the north terrace of Alne, to fight each other as a way of expressing their feelings. However after a moment of fighting, they ended up by hugging each other, and expressing their thoughts before going to the dome again, with Recon's help this time. Everything goes well until the Guardians target Recon and Leafa, ending in Recon's sacrifice to open the way, before it closes again. At that moment, hordes of Sylphs and Cait Sith Dragoons aid them, allowing the way to the door to be opened once more. Leafa throws her sword to Kirito, allowing him to break through the last blocade of Guardians, only to discover that only the game administrators may open the door. Thinking fast before another spawning Guardians attacks him, Kirito gives the system-access card to Yui, thus allowing them to open the door, and get inside.

Arriving at the top of the World Tree, Kirito and Yui finally manage to reunite with Asuna. However, they are suddenly hit by high gravity magic, which forces Yui to retreat, and are confronted by Sugou. As Sugou reveals his plans to control the human soul, he chains Asuna up and starts to molest her in front of Kirito, who is stabbed and forced to endure incredible pain. As Kirito falls into despair, he hears the voice of Akihiko, who encourages him to stand up and fight, realising the pain is nothing compared to the pain of SAO. Using Akihiko's administrative abilities, Kirito manages to strip Sugou of his high level and challenges him to a fight with no pain absorption, showing him what true pain is before finishing him off. After logging Asuna out, returning her to the real world, Kirito meets with the remnant of Akahiko's memory, who gives him an item called The Seed before leaving. After returning to the real world and giving his thanks to Suguha, Kazuto makes his way to the hospital to finally meet Asuna for real.

Rushing to the hospital Kazuto is attacked by an injured Sugou with a knife at the parking area. Kazuto manages to disarm him, and after considering everything Sugou has done, Kazuto spares his life. Kazuto finally meets with Asuna where they have a tearful reunion. On May 16, 2025, Kazuto and Asuna have returned to school, attending a special school for students who were trapped in SAO. As they have lunch, Kazuto reveals Sugou was arrested by the police after their fight and the crimes he committed were exposed by one of his employees. The 300 players that were trapped by Sugou were freed but his experiments shocked the public. Due to the scandal, Asuna's father and his higher ups resigned and shut down Alfheim Online with other VRMMORPG following suit. Later, Asuna, Kazuto and Suguha head to Agil's bar where Liz, Silica, Yoruko, Kains, Sasha, Yulier, Thinker, Klein and his guild are waiting, and they have a party to celebrate Kazuto for freeing them from SAO. Kazuto gives Agil "The Seed" to be analyzed which is revealed to be a program that allows anyone with a server to create their own VRMMORPG and it allows to transfer players to other VRMMORPG easily. «The Seed» is uploaded to the internet which revives the VRMMORPG genre. Later that night in Alfheim Online, now run by a new company, Kirito meets up with Leafa where they share a dance in the sky. Leafa decides to leave since she feels she cannot keep up with her brother but Kirito reveals his character stats have been reset. As a surprise, the floating castle Aincrad from SAO has been brought into Alfheim Online which Kirito then declares he intends to finish clearing all 100 floors. With their friends from SAO and ALfheim Online flying towards the castle, Leafa, Kirito, Asuna and Yui join them.

Suguha is revealed to be afraid of water. Thus, Asuna, Rika, and Keiko gather at the SAO Survivor School to teach her how to swim. Meanwhile, Kazuto is called for emergency counseling at the school, but, once there, he finds out that it had been a ruse for Kikuoka Seijirou to meet him to talk about the SAO and ALO incidents. During breaks between swimming practice, Suguha asks the other girls how they had met Kirito, so they tell her their stories. Later, in ALfheim Online, the team go on an underwater quest. They had to find a pearl, which was actually an egg. The NPC, who appeared to be an old man, transforms into a Kraken and demands the fairies to give him the egg. Although the fairies try to fight the beast, they find out that the boss is stronger than even Aincrad Floor Bosses. Suddenly, Leviathan the Sea Lord appears and scares off the beast. He then takes the egg to hide it again, and sends the team home on a whale.

On November 9, 2025; during the stream of «This Week's Winners», featuring XeXeeD and Yamikaze, the winner and runner up of the recently held 2nd Bullet of Bullets tournament, in a bar in SBC Glocken, a cloaked man calling himself Death Gun shoots the image of XeXeeD during the stream and moments later, XeXeeD is disconnected from the show. Nearly one month later, on December 7, 2025; Kirigaya Kazuto meets up with Yuuki Asuna at the East Gardens of the Tokyo Imperial Palace for a date. During the date, he has a flashback of his meeting with Kikuoka Seijirou from about four hours before. During the meeting, he was told about the Death Gun incident and asked to investigate it by finding Death Gun in Gun Gale Online. Meanwhile, in Gun Gale Online, Sinon shoots a player from a monster hunting party.

On September 14, 2025; Sinon acquired the PGM Ultima Ratio Hecate II by defeating a boss-class monster in a dungeon beneath SBC Glocken. Three months later, on December 7, 2025; Sinon, who had been invited to Dyne's PvP squadron two weeks before, was called upon to kill the supposedly only person in a PvE party that had a live-ammunition gun and posed a threat in PvP. Although Sinon successfully sniped the player with a minimi, a new player in the party turned out to be a hired bodyguard, named Behemoth, who was armed with a GE M134 Minigun. Sinon decided to personally kill the bodyguard, as she believed that he was strong thus killing him would help her become stronger. Meanwhile, in ALfheim Online, Leafa, Lisbeth and Silica were hunting mobs to get materials for Lisbeth, while Kirito and Asuna were enjoying their time together, until Kirito decided to tell Asuna about converting his account to Gun Gale Online.

Two days after the events in Gun Gale Online, Asada Shino, the person controlling the avatar Sinon, was in the market district, when she was approached by Endou's group and forced to come to an alley where they could demand money from her. As Shino did not accept their demands, Endou made an imitation of a pistol with her hand, causing Shino to have a panic attack. Before Endou could leave with Shino's stuff, Shinkawa Kyouji pretended to be bringing a police officer, scaring off the delinquents. Kyouji then accompanied Shino to a cafe where they had a conversation about Gun Gale Online. After the conversation, Shino returned home, where she tried out holding a model «Procyon SL» to test whether her experience with Behemoth had helped her with her phobia of guns, but was disappointed that the result was the same. Meanwhile, Kazuto arrived at Toritsu Central Hospital, from where he logged into Gun Gale Online while his body was left to the care of Nurse Aki in case the rumour about Death Gun's ability was true.

After logging in to Gun Gale Online, Kirito found himself within the capital city SBC Glocken. To his surprise, he ended up with a very feminine avatar. After hopelessly navigating the city, Kirito decided to ask a person he noticed for directions. However, he was surprised when the person turned out to be a girl, named Sinon. Mistaking Kirito for another girl player and empathising with "her" as a beginner female, Sinon showed Kirito the way to a general gun store. As Kirito did not have enough money, he asked if there was an easy way to earn money, so Sinon told him about one of the gambling games around. After Kirito won the Untouchable! game and won over 300,000 credits, Kirito bought a Kagemitsu G4 photon sword due to not having much experience with guns. Under Sinon's advice, he also bought an FN Five-Seven pistol and then went to a shooting range to practise firing. After the two were done shopping and left the store, Sinon noticed that they only had 10 minutes until the Bullet of Bullet registration would be closed. While running to the registration, Kirito noticed a place to rent a buggy and used one to get to the registration on time.

After arriving at the government office, Kirito and Sinon began registering for the Bullet of Bullets tournament. Seeing that the registration required filling in the player's real life contact details in order to be eligible for real life prizes, Kirito was tempted to write them in, but managed to restrict himself. Kirito was then led to a dressing room to prepare for the tournament, but Kirito only realised what the room was for when Sinon started undressing. Trying to look away, Kirito quickly revealed to Sinon that he was a guy. Later, Sinon reluctantly explained to Kirito how the tournament worked. Kirito's first match was against a player named Uemaru. After Kirito realised that he could use the Bullet Lines to predict the trajectories of Uemaru's bullets and then slice them with his photon sword, Kirito won the match by stabbing Uemaru in the chest. After returning to the waiting room, Kirito was approached by the mysterious player calling himself Death Gun.

After his encounter with Death Gun, Kirito realised that Death Gun was a member of Laughing Coffin in Sword Art Online. After Death Gun took his leave, Kirito recalled the events of the crusade against Laughing Coffin in Sword Art Online. During the crusade, the clearers were ambushed by members of the Laughing Coffin and a massacre ensued. As the clearers hesitated killing the red players, several clearers died, causing Kirito's to kill Laughing Coffin members in anger. By the end of the crusade, 21 members of Laughing Coffin were killed, while two of those were killed by Kirito himself. Kirito's thoughts were then interrupted by Sinon who remarked that he looked awful and wondered if he would be able to reach the finals at that rate. After seeking comfort in Sinon's hand, Kirito was teleported to his next match during which he regained his fighting spirit. Some time later, after defeating Stinger, Sinon was teleported to the block finals where she would face Kirito. To her surprise, Kirito did not even try to win the battle, greatly angering Sinon. Realising this, Kirito offered to have a duel to settle the match. By predicting where Sinon would shoot via following her eyes, Kirito managed to get close and forced Sinon to resign.

In the Kirigaya residence, Suguha showed Kazuto news about the participants of the Bullet of Bullets tournament, among which was Kazuto's avatar's name. Although Kazuto tried to hide the fact that he converted to Gun Gale Online, Suguha told him that she had already found out about it from Asuna. After a flashback of Kazuto's talk with Asuna the previous day, Suguha told him that she was worried, as Kazuto had a scary face when he came back home last night. Kazuto then calmed Suguha down by promising that he would be back. Meanwhile, Shino was venting her anger about Kirito to Kyouji. Kyouji then told her that she was not acting like her normal self and, after a short conversation, tried to hug her, but was pushed back. At the hospital, seeing that Kazuto was troubled by something, Aki offered a free counselling session. When Kazuto tells her about how he killed red players in Sword Art Online, Aki told him that she could not help him with that burden, but reminded him that he killed them to protect others. After calming down, Kazuto logged into Gun Gale Online. Meanwhile, in ALfheim Online, while Asuna and the the others were fighting a monster, Asuna got distracted and barely managed to chant a healing spell on time. In Gun Gale Online, Sinon met Kirito at the governor's office by chance.

After much persistence, Kirito was able to convince Sinon to tell him the details of the Bullet of Bullets royale. After the explanation, Kirito stopped Sinon from leaving and then asked her whether there were BoB participants that she did not know about and found out that, aside from him, there were three other players who had not participated in the former tournaments. Later on, during the tournament, after sniping Shishigane, Sinon moved to a safe place where she checked on the satellite scan. She noticed that the closest players, aside from Lion King Richie, were Dyne and Pale Rider, thus she decided to target them. Having found a sniping position on the west side of the bridge that Dyne had crossed, she was preparing to take action, but then heard a noise and realised that someone had closed in on her from behind as well. When she tried to draw her side arm, she was stopped by the player, who was revealed to be Kirito. He then asked Sinon to not take any action and just watch Dyne and Pale Rider's battle. After Pale Rider defeated Dyne, he was shot with a silent stun bullet and, after several moments, the shooter, Death Gun, came from the bridge.

In Kirito and Asuna's rented home in Yggdrasil City, Asuna and the others were watching the live broadcast of the Bullet of Bullets tournament via MMO Stream. As Kirito was not shown by any camera, they were drawn by an interesting battle between Dyne and Pale Rider. However, after Pale Rider defeated Dyne, he was struck with a stun bullet fired by a player in a cloak. Sinon attempted to shoot the player in a cloak, but he managed to dodge the bullet and then he shot Pale Rider with his pistol. When Pale Rider got up, he suddenly fell down again and seemingly got disconnected. The player in a cloak, Death Gun, then looked up to the camera and introduced the power himself and his gun to the viewers, finishing his monologue with the catchphrase used by PoH. After hearing this catchphrase, Klein recognised him as a member of Laughing Coffin. Meanwhile, Sinon attempted to find out the name of the cloaked player, but he was not shown on the satellite scan, thus Sinon assumed that he had went underwater. The two decided to follow the player, but were then interrupted by Kakouton who came after seeing them on his satellite scan terminal. While Kirito blocked Kakouton's bullets, Sinon used her sniper to kill him. The two then proceeded towards the Lost City. However, since they could not find him along the way, they decided to look for him during the next scan and, after a discussion, decided that if both Sterben and Juushi X (銃士Ｘ,Jūshi X?) were present in the city, they would go after Juushi X, as his name sounded like Death Gun (死銃,Shijū?) backwards. During the scan, they found Juushi X at a stadium, while Sterben was not shown as being in the city. The two rushed to the stadium and, after confirming that there was a sniper in the stadium, decided to split up. However, while Sinon was going to a sniping position, she was shot with a stun bullet. Death Gun, who was actually Sterben, appeared moments later after disabling his optical camouflage mantle and then claimed that he was going to kill her. Sinon attempted to take out her side arm, but, after seeing that Sterben was carrying the Type 54 Black Star, she dropped her weapon and the sound of a gun firing could be heard.

As Sterben was about to shoot Sinon, he was interrupted by Kirito, who shot him with a sniper and then threw a smoke grenade, which forced Sterben to retreat. Kirito then grabbed the petrified Sinon and her sniper and ran for a nearby buggy and horse rental point. He put down Sinon in the only working buggy and then told Sinon to shoot the only functional mechanical horse to make it unusable. However, Sinon could not exert force on the trigger and they were caught up to by Sterben, who then took the mechanical horse to chase them. During the chase, after Kirito drove through a ramp, he helped Sinon pull the trigger. Though Sinon missed Sterben and hit the fuel tank of a truck, the explosion of the truck forced Sterben to abandon his horse and thus allowed Kirito and Sinon to escape. The two then drove into the desert, where they found a cave that they could hide in and avoid the next satellite scan. Inside the cave, both Sinon and Kirito told each other about having killed someone in the past.

After hearing that Kirito had killed people in Sword Art Online, Sinon asked him how he was able to overcome the memories of the people he killed, but Kirito revealed that he did not overcome the memories and instead accepted the weight of them, as it was the minimum that he could do to atone for his actions. Kirito and Sinon then began discussing about Death Gun and his victims. While thinking about how Death Gun was able to stop the heart of players by shooting them in the game, Kirito realised that Death Gun did not shoot him with the pistol, but with the sniper instead. Based on this, Kirito deduced that Death Gun had to make preparations in real life to be able to kill the players with his pistol. He then remembered that players could input their real life details in the Governor's Office and that someone could have seen the details being input, as it was an open space and the terminals did not offer much privacy. Kirito then brought up the idea that Death Gun could have used his mantle to spy on other players without being noticed. After some thinking, Kirito realised that Death Gun was actually more than one person: one shot the player in game, while the other killed the player in real life by injecting them with a lethal drug. Meanwhile, Chrysheight came to ALO under Asuna's request and, after Yui revealed all the information on the incident that she had gathered, Chrysheight explained the situation to Asuna and the others. Asuna then requested to know of Kazuto's whereabouts and decided to go to him in real life. Back in the game, Kirito and Sinon decided on a course of action and were surprised to find out that they were being filmed by one of the cameras.

After checking the map, Kirito found out that twenty four players had already been killed, while only Yamikaze and himself were shown on the map. Seeing as, even accounting for Sinon, Sterben and Pale Rider, the number of players killed and still alive did not match the total, Kirito speculated that Death Gun had more than one accomplice in charge of the killings in the real world. Fearing that Yamikaze might also be a target, Kirito and Sinon decided that Kirito should be the bait, while Sinon sniped Yamikaze and Sterben from a distance. Some time later, while Yamikaze was closing in on Kirito, Sterben attempted to kill Kirito. Sensing the killing intent of the player killer, Kirito managed to sense where he would be shot from and barely managed to dodge the bullet. Noticing a sniper shot, Yamikaze immediately hid behind an obstacle for cover, but he was then shot by Sinon and killed. After handling Yamikaze, Sinon turned her attention to Sterben, but, as she had already used up her no-Bullet Line shot, Sterben was able to see her targeting him. The two of them fired at each other at the same time and, while Sterben managed to destroy Sinon's scope, Sinon managed to destroy Sterben's sniper. However, as Kirito was about to strike Sterben, the masked player drew out an estoc and countered Kirito's attack. After a conversation, Sterben began assaulting Kirito with overwhelming speed.

While watching Kirito's unsuccessful struggle with Sterben, Sinon wondered if there was anything that she could do to help now that her scope was destroyed and she thus could not snipe. Meanwhile, while trying to hold out against Sterben's overwhelming speed and get an opening to counter attack, Kirito tried to recall the name Sterben had in Sword Art Online. Just as he was about to be struck again he recalled, based on Sterben's red eyes, that the player used to be called «Red-eyed XaXa». Surprised by hearing his name, Sterben missed his target. Then, while his sense of judgement was slowed down, Sinon aimed a Bullet Line towards Sterben, causing him to instinctively avoid it, even though Sinon would not have shot him. During this opening, Kirito tried to counterattack, but Sterben used his optical camouflage to disappear. At this moment, Kirito felt the warmth of Asuna's hands and remembered about the FN Five-Seven that he had as his side-arm. He then used the pistol to shoot at Sterben, causing his camouflage to malfunction, and used his photon sword to slice through Sterben. In the aftermath, Sinon and Kirito exchanged contact details and Sinon decided to end the tournament with a Gift Grenade, allowing them both to be the winners. Back in her apartment, Shino checked for intruders, but instead found Kyouji at the door. However, after a conversation with him, Kyouji began acting strange and tried embracing Shino, causing her to push him off her. Kyouji then took out a syringe of a lethal drug, called succinylcholine, and revealed that he was one of Death Gun's accomplices and that he intended to inject the drug into her so that they could be reborn in another world. Shino managed to break free and tried running out of the apartment, but, as she was about to open the door, Kyouji caught her. Just then, Kazuto ran into the room and attacked Kyouji.

While Kazuto tried to defend himself against Kyouji, he left an opening for Kyouji to attempt to inject him with succinylcholine. Instead of running away, Shino returned inside and knocked Kyouji out with a stereo. Shino then checked on Kazuto's condition, but found out that there was an electrode stuck at the part of his chest where Kyouji had attempted to inject him with the drug and that the electrode protected him against the needleless syringe. Several days later, Shino was called out by Endou, who again tried to demand money from her. As Shino refused the demand, Endou took out a model gun and threatened Shino. However, after Endou unsuccessfully attempted to fire with it, Shino took the gun from Endou, showed her that the safeties needed to be disabled to fire and then shot a can with it before returning it back to Endou. As Shino was about to leave the school grounds, she saw that Kazuto was waiting for her near the entrance and drawing unwanted attention. Kazuto first drove Shino to a cafe to meet with Kikuoka Seijirou about the Death Gun incident. After that, Kazuto took Shino to the Dicey Cafe, where he introduced her to Asuna and Shinozaki Rika (Lisbeth). Kazuto then revealed that he had told the two girls about Shino's past and explained that he had them help him with finding a certain person that she should meet. The person was revealed to have been a woman, named Oosawa Sachie, who was the post office worker threatened by the robber that Shino killed. The woman thanked Shino for saving her life and told her that she was pregnant at the time, so Shino had also saved the life of her daughter, Mizue. Kazuto then explained that he wanted Shino to think about the people that she had saved by killing the robber and thus be able to forgive herself for it.

On December 28, 2025; Kirigaya Suguha showed her cousin, Kirigaya Kazuto a news article about the legendary item, the «Holy Sword Excalibur», being discovered in ALfheim Online. Without delay, he called Asuna, Klein, Lisbeth, Silica and Sinon to challenge the dungeon in the sky of Jötunheimr. After preparing their items at Lisbeth's arms shop and purchasing potions for the adventure, the group entered Jötunheimr via a secret passageway in Alne. At the end of the tunnel, they reached the top of Jötunheimr and Leafa called Tonkii, a flying evil-god-class monster that they had befriended several months ago. The group climbed on Tonkii's back and asked it to ferry them to the ice dungeon. However, along the way, Tonkii suddenly dived and stopped at an altitude where they could see the ground. There they saw that players were cooperating with the humanoid evil-god-class monsters to massacre Tonkii's kin, the beast evil-god-class monsters. As they were watching the scene, a giant NPC, the «Queen of the Lake» Urðr, appeared behind them. The NPC explained that the massacre was ordered by the king of the giants, Thrym, who once threw the Holy Sword Excalibur into Urðr's Spring and caused the world of Jötunheimr to turn into an icy wasteland. She then explained that if all of Tonkii's kin were slaughtered, she would lose her power and this would allow Thrym to invade the land of the fairies, Alfheim. To prevent this, Urðr requested the fairies to retrieve the Holy Sword Excalibur from the bottom of the ice dungeon, called Thrymheim.

At the entrance to Thrymheim, Yui explained that the quest they were given was created by the Cardinal System's «Automatic Quest Generation Function» and that if they did not succeed in their quest, a final war event, Ragnarok, would be triggered. Some time later, at the end of the second floor of Thrymheim, the group encountered two minotaurs, one of which had high resistance for magical attacks, the other for physical attacks and would change places to heal after having suffered too much damage. As the party did not have any mages with offensive spells, they relied on Sword Skills that could deal elemental damage in addition to physical damage, but left the player rigid for a few seconds after the skill ended. With Kirito revealing his new technique of using consecutive Sword Skills with each of his swords to avoid the period of rigidity, they were able to defeat the two minotaurs. Later, after defeating the boss guarding the entrance to the lowest floor of the castle, the fairies encountered an NPC woman trapped in an ice cage along the way. Although the group insisted that it was a trap and planned to avoid her, Klein ignored their advice and freed the woman, who was revealed to be Freyja. Instead of running away, Freyja asked to join the group and Kirito reluctantly agreed to the request. After preparing for the final battle by recharging their buffs, the group entered the throne room where they met the king of the frost giants, Thrym.

The battle against Thrym began with Thrym's attack. Surviving the initial attacks, the fairies and Freyja managed to bring down Thrym's HP to two bars. However, after they survived a breath attack, Freyja approached Kirito and Leafa and requested them to find her family treasure, a golden hammer, hidden within the room, as they would not be able to defeat Thrym otherwise. Under Leafa's advice, Kirito used «Lightning Fall» to find the hammer hidden in the piles of treasure. Unexpectedly, once the hammer was returned to Freyja, she transformed into a giant man, the god of thunder, Thor. With Thrym's attention occupied with Thor, the fairies rushed to help Thor with their own attacks. Once Thrym's HP was nearly depleted, Thor finished Thrym off with his hammer. Before Thor took his leave, he rewarded Klein with a miniature replica of his hammer. At that point, the fairies found out that the quest had not yet been completed, as Excalibur had not been yet retrieved, and Yui informed them that new stairs had appeared behind the throne. At the room where Excalibur was held, Kirito successfully managed to pull out the sword from its plinth. This caused the roots of the World Tree to grow and Thrymheim to break. As the fairies were falling, Tonkii arrived to rescue them, but, as Kirito could not store Excalibur into his inventory and it was too heavy for him to jump on Tonkii with, he had to leave the sword behind. But unexpectedly, Sinon used an archer spell, called «Retrieve Arrow», to retrieve the lost sword which she then gave to Kirito, after teasing him to always remember her when he used it. The fairies were then approached by Urðr and her sisters who rewarded the fairies for their help. Back in the real world, the group met up at the Dicey Cafe where they celebrated the end of the year and the successful completion of the quest.

On December 20, 2025; Kazuto and Asuna had a date at Andrew's cafe. When they started talking about their old home in Aincrad, Andrew told them about the revealed contents of the upcoming ALfheim Online update, including the introduction of the 21st-30th floors of New Aincrad. On Christmas Eve when the update took place, Asuna challenged the Floor Boss of the 21st Floor with the hope that their old home on the 22nd Floor remained unchanged. After a fierce battle, the group managed to successfully reach the 22nd Floor. There Asuna and Kirito rushed to the place of their old home and re-purchased it. On January 6, 2026; Asuna, Leafa, Lisbeth and Silica were doing their homework at Asuna and Kirito's log house, while Kirito was sleeping on the rocking chair with Pina and Yui on top of him. As Kirito's aura of sleepiness was making everyone else sleepy, Asuna made some tea and the girls stepped outside. Lisbeth then asked if Asuna had heard about the stories about Absolute Sword. As Asuna had been away during the New Year and did not have access to the Internet, so she could not have heard such stories, Lisbeth explained that Absolute Sword was a strong player who had likely converted from another game and was challenging other players at an island on the 24th Floor. Although many players challenged them, including Leafa and Lisbeth, they were all beaten easily. However, Silica explained that players would likely continue to challenge the mysterious player as they were betting an 11-hit Original Sword Skill, having a higher combo than the previous top Original Sword Skill, General Eugene's 8-hit «Volcanic Blazer». After hearing that Kirito had also fought the player and lost, after saying something to them, Asuna decided to challenge the player herself. At that moment, Asuna noticed that it was already past her dinner time, but before she logged out, she asked Lisbeth if the player could be a former SAO player. Lisbeth answered by saying that she had asked Kirito what he thought about the player after battling them and his response was that the player could not have been an SAO player, as the «Dual Blades» skill would have been given to them instead of him.

After agreeing to meet everyone the next day, Asuna logged out and went to have dinner with her mother. During the meal, Asuna's mother, Yuuki Kyouko, told Asuna that she wanted her to transfer to a more proper school. After a lengthy conversation about it, Asuna returned to her room and thought about how she wanted to stay by Kazuto's side and how she was only able to fight for herself in the virtual world. The next day, Asuna met with Kirito on the 24th Floor of New Aincrad. As the two saw a rabbit that reminded them about the Ragout Rabbit, they recalled the time when Kirito first came to Asuna's house in Selmburg. They then noticed players flying to the island where Absolute Sword was holding their duels. After Kirito told Asuna that Absolute Sword was strong, she asked him what he had said to them during their duel. Kirito explained that he had asked them whether they were truly living in the virtual world. As Kirito finished sharing his impressions of the mysterious player, they were interrupted by Leafa, Lisbeth and Silica, who reminded them that Asuna had a duel to get to. At the island, Asuna found out that the mysterious player was actually a girl named Yuuki. Pushed by Lisbeth, Asuna challenged Yuuki and soon found out how skillful she was. Deciding that she would not give up, Asuna went full out. As the battle raged on, Asuna punched Yuuki while their swords were crossed and then used the window to activate a rapier Sword Skill, Quadruple Pain. To her surprise, Yuuki skillfully managed to block her fast attacks and then activated her own Sword Skill. Suffering heavy blows, Asuna activated her Original Sword Skill, Starry Tear. However, while she had used up her last attack of Starry Tear, Yuuki's Sword Skill was still ongoing. Although Asuna was prepared to be defeated, Yuuki stopped the attack just before it reached her. Yuuki then stated that she was satisfied with the duel and gave her hand to Asuna. Yuuki then took Asuna to outside Aincrad where she asked for her help.

After Yuuki took Asuna to an inn in Ronbaru, she introduced her to the other members of the Sleeping Knights: Jun, Nori, Siune, Talken and Tecchi. Yuuki then told her that the guild wanted her help in defeating the next Floor Boss with just one party. Siune explained that the group wanted to defeat the boss in order to etch all of their names on the Monument of Swordsmen, as they would not be able to adventure together after winter and thus decided to make a memory that they would never forget. After some thinking, Asuna agreed to help and meet with the Sleeping Knights the next day. Some time later, while Asuna was walking at the Teleport Gate plaza, she was disconnected from the game by her mother who then told her that she was late for dinner. After an unpleasant conversation with her mother, Asuna headed to a park in another residential area. There she considered calling Kazuto, but decided that she did not want to expose her weakness to him. The next day, she met up with the Sleeping Knights and they easily managed to reach the boss room. However, Asuna detected several players hiding near the boss room. As the players claimed that they were just waiting for their friends, the group entered the boss room. But, during the battle, Asuna noticed that the party were actually spying on their battle to study the boss without sacrificing their own men. After the Sleeping Knights and Asuna respawned in Ronbaru, Asuna told the others what she had discovered and they decided to rush to the boss room again before the guild they encountered had enough time to gather a raid group. Although the guild had not manage to prepare yet, there were enough players gathered at the boss room door to seal off the area. As the guild rejected the request of the Sleeping Knights to let them try again, even though the large guild was not yet ready, Yuuki declared that they would fight it out and assaulted the raid group's leader. At that point, the rest of the boss raiding guild came to the scene, but then Kirito who was following them ran past them via a wall and blocked their path.

After Kirito blocked the raiding guild's reinforcements, three mages of guild fired multiple magical projectiles at him. However, he used «Deadly Sins» to break all seven projectiles. As the reinforcements got into formation for battle, Kirito told Asuna that he would hold them off for three minutes with the help of Klein. In the meantime, the Sleeping Knights engaged the guild's forces blocking the path to the boss room. But, seeing that their assault was rendered useless by the intervention of the guild's healers, Asuna asked Siune to manage the healing herself and used «Flashing Penetrator» to break through to the healers, while killing the group's leader. After the healers were disposed of, the remained of the players were easily defeated, allowing Asuna and the others to enter the boss room. During the boss battle, Talken's spear was thrown into the air by the boss and it accidentally hit a crystal where the boss's two heads connected. Seeing that this caused the boss to assume a guard stance, Asuna deduced that it might be its weak point and tested it out by firing several ice pillars at the same spot. Confirming her deduction, Asuna left the healing to Siune to tell Yuuki to use a Sword Skill at the weak spot. Following Asuna's suggestion to use Tecchi as a stepping stone, Yuuki defeated the boss with her signature Original Sword Skill. After the battle, the group agreed to celebrate at Asuna's player home. While conversing about various things, Asuna asked whether she could join the Sleeping Knights, but, seeing that it resulted in an unpleasant reaction, she decided to change the topic and reminded everyone about the Monument of Swordsmen. At the monument, everyone took a picture and Yuuki accidentally called Asuna as her elder sister. Since she had also done the same in the boss room, Asuna pointed this out to Yuuki. Unexpectedly, Yuuki started crying and abruptly logged off.

Three days after Yuuki abruptly logged out from ALfheim Online at the Monument of Swordsmen, Asuna met with Siune at the Ronbaru inn to ask what happened to Yuuki. Siune informed her that they were not able to contact Yuuki either and explained that Yuuki most likely did not want to see Asuna for her sake. After a short conversation, Siune abruptly logged out, asking Asuna to forget about them. At school, Asuna was messaged by Kazuto to meet at the rooftop. There, Kazuto asked Asuna if she really wanted to see Yuuki despite the Sleeping Knights asking her not to. After Asuna confirmed this, Kazuto gave her the address for a hospital where a medical FullDive machine, the Medicuboid, was being tested. At the hospital, Asuna asked the nurses if she could meet a patient named Yuuki, but, as just the name was not enough, Asuna explained that Yuuki was the person testing the Medicuboid. A senior nurse immediately reacted and asked for Asuna's name and then asked her to wait at a bench. Several minutes later, Asuna was approached by doctor Kurahashi, Yuuki's doctor. Kurahashi took her to a lounge upstairs to talk. He then expressed his surprised that Asuna was able to find the hospital and told her about the Medicuboid and that it was expected to be used for patients in terminal care. Kurashi then told Asuna that Yuuki allowed him to tell Asuna about her, but claimed that Asuna might regret hearing it. As Asuna asked him to continue, Kurahashi took Asuna to the room next to the Medicuboid testing room and explained that Yuuki was suffering from the Acquired Immunity Deficiency Syndrome (AIDS) due to an infection via blood transfusion during a complicated labour. He then told her that Yuuki continued to fight the disease, but in the 4th school year, her immune system collapsed and she was hospitalised. After Asuna asked why Yuuki started using the Medicuboid, Kurahashi explained that he was the one who offered the testing to her to have her put in a clean room where she would not risk further infection. He also told her that Yuuki had been living inside the machine for three years straight, not returning to the real world at all. Asuna then asked whether Yuuki had a sister and found out that her elder twin sister had passed away the year before. Seeing Asuna cry, Yuuki used the speakers connected to the Medicuboid to tell Asuna not to cry and to ask her to meet at the place where they first met in ALfheim Online. Asuna used the AmuSphere in the next room to log in to the game and rushed to Yuuki's location. There, the two talked and Asuna heard that Yuuki had a wish of going to school again. Suddenly, Asuna came up with an idea of how Yuuki could go to school.

On January 12, 2026, the day after Asuna reunited with Yuuki, Kazuto and two other mechatronics course students were working on tuning Kazuto's Bidirectional Communication Probe for Yuuki to use to take part in the lessons at the SAO Survivor School. As lunch break was almost over, Asuna asked the boys to hurry up. After the tuning was completed, Asuna took the shoulder-mounted probe to the faculty office to introduce Yuuki to the teacher of the upcoming lesson. Asuna then took Yuuki to class, where she soon became the centre of attention. As the lesson began, everyone took their seats and Yuuki was asked to read a passage. After the end of the lessons, Yuuki thanked Asuna for the opportunity to visit a school, but Asuna told her that she could come to school every day with her. Asuna then asked Yuuki whether there was any place that she wanted to go to as well and Yuuki answered that there was one place that she wanted to visit. As requested, Asuna took Yuuki the old Konno residence. As Asuna still had some free time, Yuuki talked about the memories she had at the house and also mentioned that the house would be torn down soon, so Yuuki wanted to see it one last time. Asuna then suggested that when Yuuki turned sixteen, she should marry someone she liked to have the person protect her home. Yuuki laughed and said that she did not have anyone that she would want to marry, but then made a joke proposal to marry Asuna and asked her to be the wife so that she would not become Yuuki Yuuki. After the joke, Yuuki thanked Asuna again and said that by seeing her house she realised how her mother had been surrounding her with her feelings. Asuna then told Yuuki about the relationship she had with her own mother and asked Yuuki how to be as strong as her. However, Yuuki claimed that she was not strong, but she did not feel like she had time to waste, so she would always be honest with her feelings. As Yuuki recommended Asuna to talk with her mother and share what she felt, Asuna decided to show her world to her mother by asking her to use an AmuSphere. Reluctantly, Kyouko agreed and used Asuna's sub account to log in. In the Forest House, Asuna showed her mother the view outside the house, reminding Kyouko about the home of her parents. Asuna then reminded Kyouko about the time when the whole family went to Kyoto, while Asuna went to Kyouko's parents' home instead. Asuna told Kyouko that her parents were not angry that Kyouko did not come to visit them. Instead, they told Asuna that Kyouko was their treasure and how they were happy with how well Kyouko was doing, but they would protect their home so that Kyouko would have a place to return to if she got tired. Asuna then finished by saying that she lately realised how life was not about just doing things for oneself and how the happiness of others could make one happy as well, thus she wanted to remain in her current school where she could support the ones she loved. The next morning, Kyouko told Asuna that if she planned to support someone, she had to be strong herself, thus she would have to work hard on her grades to get into university and whether Asuna would have to transfer would depend on her progress.

Three days after Asuna talked with her mother, Asuna held a barbecue at the Forest House. During the barbecue, Jun brought up that they could beat the 28th Floor boss and the enthusiastic group decided to take a tour through the 28th Floor Labyrinth where they ended up beating the boss. Over the following months, Yuuki continued to attend classes at the SAO Survivor School, the fairies had a race in Alfheim, the Sleeping Knights and Asuna defeated the 29th Floor boss, a swordsmanship tournament was held in ALfheim Online which Yuuki won after a fierce battle with Kirito, Asuna kept her promise and worked hard on her grades, and organised a trip to Kyoto, with all the members of the Sleeping Knights using Kazuto's probe to take part in the trip. However, near the end of March, Asuna received a message from Kurahashi that Yuuki's condition was worsening. Asuna rushed over to the hospital, but found out that Yuuki's condition was critical and that nothing more could be done. While holding Yuuki's hand, Asuna realised that Yuuki wanted to return to the virtual world, thus she asked Kurahashi to allow her to FullDive. On the 24th Floor, at the island where Asuna and Yuuki first met, Yuuki created a scroll for her Original Sword Skill and passed it to Asuna in hopes that it will protect her. Just then, the members of the Sleeping Knights arrived to cheer Yuuki in her final moments. The Sleeping Knights were followed by Kirito, Klein, Leafa, Lisbeth, Silica, Sinon and Yui. Finally, a large group of fairies of various races gathered at the island and Asuna revealed that she had notified everyone so that Yuuki would not have a lonely farewell. Yuuki then told Asuna how she had always asked herself what was the reason for her living if she was destined to die anyway, but then said that she had found the reason, as her last moments were truly fulfilling. After Asuna promised to meet her in another world, Yuuki peacefully passed away. A week later, at Yuuki's memorial, Asuna met with Siune whose condition was improving. After they talked about Yuuki, Kazuto and Kurahashi joined their conversation. As Kazuto and Kurahashi explained that they were talking about Kazuto's probe's application for medical FullDive technology, Asuna asked about the tests for the Medicuboid. Kurahashi revealed that Yuuki had provided more than enough data and claimed that Yuuki should get a reward like the person who provided the initial designs. As Asuna was surprised that the Medicuboid designs came from an external helper, Kurahashi revealed that the helper was Koujiro Rinko. The shocked Kazuto then revealed that Rinko was the person who took care of Kayaba Akihiko during the SAO incident, thus the Medicuboid designs actually came from Akihiko. Some time later, the group had a picnic.

In Japan, all 9 volumes of season 1 discs were released between October 24, 2012 and June 26, 2013, while the Extra Edition volume was released on April 23, 2014. Each volume is divided into 3 versions: Limited edition Blu-ray Discs, Limited edition DVDs, and Regular Edition DVDs.

Limited edition versions include a character commentary special episode, called "Sword Art Offline" for each volume, a non-credit opening song for volumes 1 and 6, a non-credit ending song for volumes 5 and 9, and an original soundtrack for volumes 4 and 7, respectively. Volume 1 and 9, as well as the Extra Edition volume special editions were also bundled with a short story novel, called The Day Before, The Day After and Rainbow Bridge respectively. Each volume also has an episode given with an audio commentary by the creators and Japanese casts. There are also specials, for example, 16-page deluxe booklets, included.

An example of the specials' art.

Those who purchase Volume 1 and Volume 6 BD/DVD from specified shops can get a collection box that can store discs of that arc, with an illustration drawn by abec wrapped around it. Those who buy all volumes together from these shops can get a cast symposium CD. There are also many different shop-specific specials that can be obtained by buying these discs, the content included in these specials varying based on the shop the discs are purchased from.

Discs for the Extra Edition are also available separately in April 2014, with a limited edition version featuring bonuses similar to those in season 1, including a Sword Art Offline episode, a short story novel, a 16-page deluxe booklet, digital character design and so on.

Unlike the Japanese Blu-ray disc version, the American Blu-ray discs for season 1 are packed in 4 BD-BOX sets/DVD Volumes, 2 sets for each arc. Original Soundtracks, audio commentary and special episodes are also included in BD box sets. Both BD box sets and DVD volumes have a non-credit opening/ending song included. Numerous other material are also included in both versions, although the BD boxset has more such material, including a 16-page deluxe booklet, English cast interviews and so on.

The season 2 disc release in Japan will be starting from October 22, 2014. Like the season 1 discs, limited version BDs and DVDs will include Sword Art Offline, commentary audio channels, booklets, and so on. The original soundtracks of SAOII come with BD Volume 3 and 7.

A mock TV news is held by Kirito and Asuna, featuring some highlights of episodes 1 and 2 and having Klein as a special guest. Then Kirito tries to do Life Counseling, but the client (Klein) is not satisfied.

Features highlights of episodes 20, 21 and 22, with Sakuya and Alicia Rue as the special guests. In the first 7 minutes of the episode, the show reminiscences about Kirito's death in ALO, with Kirito standing in a coffin.

↑ 1.01.1The English dub version of episodes 4-25 was initially released in English on DVDs and Blu-Rays. The airdates listed with "(DVD/BD)" refer to the episode's initial release on DVDs and Blu-Rays, while dates marked with "(TV)" refer to their first English television airings on Adult Swim's Toonami block.